1. Field of the Invention
The present invention relates to a fan in an induction motor for dissipating heat generated in the motor.
2. Description of Related Art
When a motor is rotating at a high speed, a huge amount of heat is generated. In order to dissipate the heat and cool down the wire coils thereof, usually a fan is provided to rotate with the motor shaft synchronously for cooling purpose. In a prior art as shown in FIGS. 1 and 2, a fan (3) is attached onto a motor shaft (2) in an induction motor (1). Although the rotating fan is able to direct heat-dissipating air currents into a motor cover shield (6), it is unable to cool the motor effectively. It is because the blades of the fan (3) are connected perpendicularly to the motor shaft (2) and directly onto an annular base plate (4). Therefore, the air current in the conventional induction motor can only be directed straightforward to the walls of the cover shield (6) (as shown in FIG. 1). Thus, a turbulent phenomenon occurs and it results in that the cooling air is unable to flow directly onto the main wire coils in the motor (1). This effect significantly reduces the heat dissipation and cooling of the motor. Therefore it is shown that the prior art of the heat dissipation and cooling system cannot effectively lower the temperature of the motor and might result in lowering of the motor performance and shorting of the motor life.